^Matthew Kapstein, University of Chicago Press, 2004, "The presence of light: divine radiance and religious experience", University of Chicago Press, 2004. pg 285: "the light of lights in the system of the Persian philosopher Suhrawardi"

^Hossein Ziai. Illuminationism or Illuminationist philosophy, first introduced in the 12th century as a complete, reconstructed system distinct both from the Peripatetic philosophy of Avicenna and from theological philosophy. in: Encyclopædia Iranica, Volumes XII & XIII. 2004.

^Edward Craig, Routledge Encyclopedia of Philosophy, "al-Suhrawardi, Shihab al-Din Yahya (1154-91)" Routledge 1998. Excerpt: "Shihab al-Din Yahya ibn Habash ibn Amirak Abu’l-Futuh al-Suhrawardi, known as al-Maqtul (the Slain One) in reference to his execution, and usually referred to as Shaykh al-Ishraq after his school of Illuminationist philosophy (hikmat al-ishraq), was born in AH 549/AD 1154 in the village of Suhraward in northwestern Iran."